Replacing in-dash tachometer

[Elliott]

I need to replace the in-dash tach in my 79 vette as it registers far too high. Is that common for them to fail in that manner? Anyway, I have not looked at any manuals, but it appears to be a straight forward removal from the face of the dash. Any pitfalls or issues I need to be aware of before I start? Any recommendations on where to buy my replacement? From what little I have looked they aren't cheap.

Thanks in advance!

Elliott

 

[Don Mason]

Elliott, I am not so sure that changing the tach is going to be piece of cake you think it is. I have had the dash out of my 73 and it is pretty involved. The instruments come out from the back side and the dash has to be removed to pull the instuments. I am not fully familiar with a 79 but I don't think there is a lot of difference in how the dash goes together. I do know that all of the instruments were electronic by 79 and they were still mechanical in 73. Also if the tach works but just registers too high you may want to check to see if there is a problem somewhere else be fore your pull the entire dash to change the tach. Just something to think about.

 

[Elliott]

I wasn't aware that the dash needed to be removed. I noticed some screws on the dash and it appeared it would come out the front. I have no plans to remove the dash, that is more than what I want to take on. TX Elliott

 

[Don Mason]

I could be wrong!!It would not be the first time. Find a service manual and see for sure how the cluster comes out.

 

[bagger]

Go to www.corvetteenthusiast.com and look at their March 2010 issue. It has an article on 75-82 Electronic Tach Repair. Very informative.

 

[Elliott]

Got it. That will be very helpful. Thanks! Elliott

 

[minifridge1138]

1979 Tach can come out from the front. Not too hard, just go slowly and gently. That plastic is 31 years old and could be brittle. You'll need a phillips screwdriver, an allen wrench, and a nut driver (or socket with an extension).

The tach needle comes off just by pulling on it. Just pull straight out. Don't wiggle it.

I've only seen two failure conditions: dead, and pegged at readline.
I'm not sure if it is common for them to fail that way, but I had the same problem when i bought a replacement tach circuit board that was not calibrated. So it could just be a failed board.

I would check the distributor and the tach filter before I took the cluster apart. You can buy a 25 dollar electric tachometer from an auto parts store. Connect it to the distributor and see if that is correct. It can also be handy to have when trying to set timing, adjust mixes, etc.

 

[crause]

Can't get to March issue

Go to www.corvetteenthusiast.com and look at their March 2010 issue. It has an article on 75-82 Electronic Tach Repair. Very informative.

I tried using this link but can't get to the March issue to view this article. Any help?

 

[6880 Mike]

I tried using this link but can't get to the March issue to view this article. Any help?

Contact CE through their website and see if you can order a back issue.

 

[JohnZ]

Contact CE through their website and see if you can order a back issue.

Or call the Customer Service desk at (800) 448-3611.

 

[bagger]

Go to their website, click on digital library, scroll to March issue, click on it and go to the article. Just went there to check it out and I had no problem getting to the article. Good luck with the tach.

 

[donnie_19]

Tach and Speedo cluster can be removed from the front. Remove the bezel, remove the other plastic front piece, then 3 screws hold the tach in place. The tach has threaded posts in back that make the connection with the clips on the circuit board. Could be one of the clips not making connection.